40:2 CORRESPONDENCE OF RAY. 



attend any stndy, being diverted by pain. It is true of 

 late years I have diverted myself by searching out the 

 various species of insects to be found hereabouts, but I 

 have confined myself chiefly to two or three sorts, viz, 

 Papilios diurnal and nocturnal, beetles, bees, and spiders. 

 Of the first of these I have found about 300 kinds, and 

 there are still remaining many more undiscovered by me, 

 and all within the compass of a few miles. How many, 

 then, may Ave reasonably conjecture are to be found in 

 England, in Europe, in the East and West Indies, in the 

 whole world. The beetles are a tribe near as numerous 

 as these, and the flies of all sorts not fewer. I have now 

 given over my inquisition, by reason of my disability to 

 prosecute and my approaching end, which I pray God fit 

 me for. You that have more time before you may profit- 

 ably bestow some of your spare hours u})on such incpiiries, 

 and may probably make useful discoveries, at least may 

 reap a great deal of pleasure and satisfaction in finding 

 out and bringing to light some of the works of God not 

 before taken notice of. So I heartily bid you farewell. 



Black Notley, June 30, 1702. 



Note. — At the time when this letter was written I was 

 but a novice in the history of insects, particularly of gnats, 

 having begun my strict observations of them but the fore- 

 going spring. In order to the discovery of the process of 

 their generation, I shut up in glasses divers nym])hae and 

 aurelige of gnats, with the water in which they were pro- 

 duced ; and after all the aureliae were become gnats, and 

 the nymphse, aureliae, I found there were other nymphae 

 succeeded ; and, not having seen any eggs in the water, 

 I very inadvertently concluded that those nympha?, or at 

 least the aureliae (which I thought might be more perfect 

 animals than I afterwards found them), might lay eggs, 

 and be the parents of those succeeding nymphse. But I 

 soon found my error, and that what my friend Mr. Ray 

 saith in this letter was true, and also discovered the whole 

 process of the generation of gnats, and that this tribe of 



